This invention relates to rotary engines and rotary compressors of similar geometry and, more particularly, to improved compression seals for such rotary mechanism. Prior art of possible relevance includes the following U.S. Pat. Nos.: Bentele, 3,176,910, granted Apr. 6, 1965; Reinhart et al., 3,697,202, granted Oct. 10, 1972; and McCormick, 3,718,412, granted Feb. 27, 1973.
Side seals carried by the rotors of trochoidal type engines and peripheral or circumferential seals on slant axis rotary engines serve as compression seals in such engines. Apex seals perform the same function, while "bolts" or "buttons" provide the same function at the end of an apex seal. Such side seals and bolts as well as the ends of apex seals are rubbed against their mating surfaces, the walls of the housing of the engine, at a relatively high rate in the longitudinal direction. As a consequence, such seals are prone to scuffing and rapid wear.
The present state of the art suggests a solution may be found primarily in the selection of better materials rather than determining the cause or causes of the problem.
While normally, a bolt will not scuff before the side seals, the bolt frictionally engages the housing walls and, consequently, is a source of heat which contributes to the buildup of temperature at the ends of the side seals which do scuff.
In a like manner, according to the state of the art, apex seals are made short enough to prevent the onset of scuffing at their ends, the intentionally designed gap contributes to gas leakage which, in turn, decreases the efficiency of the engine. When such a gap is minimized to increase efficiency, when the engine is operating under severe conditions, the ends of the apex seals will approach the housing walls and initiate undesirable scuffing and wear.